His posts are a mix of his own videos and snapshots, as well as retweets of others' posts, including political figures.

Many of the videos show the signs carried by demonstrators, the news conferences that have turned into public forums, and the marches up a main Ferguson street.

"And we walk," Dorsey posted.

@Jack has posted videos and snapshots like this one of the protests.

Several of his recent posts showed the State Highway Patrol officer who has led security efforts and drawn praise for listening to and marching with demonstrators.

"The crowd constantly siding with Cpt. Johnson," he wrote of Capt. Ron Johnson. "Amazing and disarming leader."

Dorsey, who more recently launched mobile payment company Square, has also commented on Gov. Jay Nixon's decision to impose an overnight curfew. Nixon explained it is intended to halt the late-night violence and looting in which some have participated.

"I know nothing, but this feels like a missed opportunity to trust our people," he wrote, directing his post to the governor.

Jack Dorsey: Twitter, Square...billionaire

As the curfew hour neared late Saturday, Dorsey urged demonstrators to go home and denied an online rumor that he'd been arrested or detained.